When my father-in-law died suddenly, my wife invited her mother to stay with us. Our children were grown and we had plenty of room. I had known my mother-in law for twenty-two years, and she was always very proper and very reserved. She had always been nice, but we rarely spoke to one another. I always thought she didn't care for me. The first six months after she moved in were very normal. I could tell she was lonely. I would go out of my way to keep her company, and we came to enjoy each otherís company. My wife was promoted at this time, and her new job would take her out of town on business quite often. It was during one of her trips that I came home from work, and my very prim and proper mother-in-law met me at the front door wearing only black panties, a lacey black bra and silver high heels. She looked amazing, and I was shocked. I was so turned on I couldn't even speak. The next thing I knew, we were rolling around on the living room floor having the best sex of my life. Later that night as we lay in bed, she told me that she hadn't had sex for the past fifteen years and that she had often fantasized about making love to me. Well, it's been three years and we both look forward to my wife's business trips.